Is there a way to invert a wireframe?
Is this a hack?
First, give your object a vertex group, set to a very low weight for all vertices.. mine's called 'Shell_VG'
Give your object an Edge Split modifier, on all edges, followed by a Solidify Modifier, set to fill the rim, and weight the 'Shell_VG' group.

Then a Displace modifier along normals to shrink the faces, and a Mask modifier aimed at the shell vertex group, set to a higher threshold than the one you set originally.

For the pink result:

If you don't mind solid faces, you can cut out all the masking steps.